Specifications

Audio transmision
TRX-Manager does not support audio transmission many solutions to transfer the audio from
SERVER <->CLIENT has been described by users on the TRX-Manager's mailing list.
The main possibilities are the followings:
Real-time audio link
This solution requires a V/UHF link, a phone line or wireless headphones. This solution is
probably the best suited for DXing because of the quality of the audio and the lack of delay
during the transmission. It is - of course - not practicable over long distances such as through
the Internet.
TCP or UDP audio link
This solution involves telephony (VoIP) software. More popular software for HAM Radio and
DXIng are:

Skype

Mumble

IP-Sound

Rem Audio
While Skype is very easy to use, widely distributed and does not require a static IP and port
forwarding, IP-Sound has some advantages : it is a stereo-bidirectionnal software so dual RX
is possible and you can monitor your audio ; also you can choose the more suitable codec
however, it uses the less reliable UDP protocol and ... it is discontinued. Rem Audio is
promising.
The main drawback of audio processing via TCP or UDP is the delay (from 0.5s to 2s) of the
transmission which makes tuning a station in SSB or CW "acrobatic". This solution is perfect
for broadcasting in AM via the Internet but less convenient for DXing. UDP is preferable.
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